#!/bin/sh
# Compile FFdecsa in different modes to find the fastest
# This script is based on the conigure script from getstream_a84
# Copyright (C) 2012 Unix Solutions Ltd.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2
# as published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License (COPYING file) for more details.

cd $(dirname $0)

CROSS="$1"
CC="${2:-cc}"
FFDECSA_CFLAGS="-O3 -fexpensive-optimizations -funroll-loops"

MAX_MODE="PARALLEL_32_INT"

FFDECSA_MODES="PARALLEL_32_INT"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_64_2INT"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_64_LONG"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_64_MMX"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_128_2LONG"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_128_2MMX"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_128_SSE"
FFDECSA_MODES="$FFDECSA_MODES PARALLEL_128_SSE2"

# Internal variables
OUTPUT_FILE="FFdecsa.opts"
FFDECSA_DIR="FFdecsa"
LPREFIX="[FFdecsa]"
MAX_SPEED=0
TMPDIR=`mktemp -d FFdecsa.build.XXXXXXXX` || exit 1

trap "{ rm -rf $TMPDIR ; exit 1; }" INT TERM

cp $FFDECSA_DIR/Makefile $FFDECSA_DIR/*.c $FFDECSA_DIR/*.h $TMPDIR

log()  { printf "%s %-26s : %s\n" "$LPREFIX" "$1" "$2"; }
logn() { printf "%s %-26s : %s"   "$LPREFIX" "$1" "$2"; }

log "Using compiler" "$CROSS$CC"
log "FFdecsa modes" "$FFDECSA_MODES"

cpu_have() {
	# Check whether option is supported by the host CPU
	grep "^flags.* $1 " /proc/cpuinfo >/dev/null 2>&1
	eval test $? -eq 0
}

cc_check() {
	# Check whether option is supported by the target CC
	$CROSS$CC $1 -xc -o /dev/null - 2>/dev/null << EOF
int main(void) { return 0; }
EOF
	eval test $? -eq 0
}

test_ffdecsa_mode() {
	MODE="$1"
	logn "Testing $MODE"

	ERRLOG="FFdecsa_build_$MODE.log"
	MAKECMD="make -C $TMPDIR FFdecsa_test PARALLEL_MODE=$MODE FLAGS=\"$FFDECSA_CFLAGS\" COMPILER=\"$CROSS$CC\""
	eval $MAKECMD >/dev/null 2>$TMPDIR/$ERRLOG

	if [ $? -ne 0 ]
	then
		echo "ERROR: build failed, check $ERRLOG"
		(echo "$MAKECMD" ; echo ; cat $TMPDIR/$ERRLOG) > $ERRLOG
		return
	fi

	if [ "$CROSS" != "" ]
	then
		cp $TMPDIR/FFdecsa_test FFdecsa_test_$MODE
		echo "CROSS COMPILE OK: You can run FFdecsa_test_$MODE on the target machine"
		return
	fi

	RESULTS_FILE="$TMPDIR/test_results.txt"
	$TMPDIR/FFdecsa_test >/dev/null 2>$RESULTS_FILE
	if [ $? -ne 0 ]
	then
		echo "ERROR: test run failed"
		return
	fi

	grep FAILED $RESULTS_FILE >/dev/null 2>&1
	if test $? -ne 1; then
		echo "ERROR: test failed"
		return
	fi

	SPEED=`grep "speed=.*Mbit" $RESULTS_FILE | sed -e 's/^.*=\([0-9]*\)\.[0-9]* Mbit.*$/\1/'`
	echo "OK $SPEED Mbit/s"
	if [ $SPEED -gt $MAX_SPEED ]
	then
		MAX_SPEED=$SPEED
		MAX_MODE=$MODE
	fi
}

# Check CPU and compiler flags
if cc_check -march=native
then
	FFDECSA_CFLAGS="$FFDECSA_CFLAGS -march=native"
elif cc_check -march=pentium; then
	FFDECSA_CFLAGS="$FFDECSA_CFLAGS -march=pentium"
fi

OPTS=""
FLAGS=""
for flag in mmx sse sse2
do
	if cpu_have $flag
	then
		OPTS="$OPTS $flag"
		if cc_check -m$flag
		then
			FFDECSA_CFLAGS="$FFDECSA_CFLAGS -m$flag"
		fi
	fi
done

log "Host CPU" "$(uname -m) $OPTS"
log "FFdecsa CFLAGS" "$FFDECSA_CFLAGS"

for MODE in $FFDECSA_MODES
do
	test_ffdecsa_mode $MODE
	make -C $TMPDIR clean >/dev/null 2>&1
done

log "Choosing PARALLEL_MODE" "$MAX_MODE ($MAX_SPEED Mbps)"

echo "# This file is included from Makefile
DECRYPT_LIB = ffdecsa
FFDECSA_OBJ = FFdecsa/FFdecsa.o" > $OUTPUT_FILE
echo "FFDECSA_MODE = $MAX_MODE" >> $OUTPUT_FILE
echo "FFDECSA_FLAGS = \"$FFDECSA_CFLAGS\"" >> $OUTPUT_FILE

rm -rf $TMPDIR